Take a look at the figure below. The two circles in the geometry have centers at the origin and radii of 1.0 and 1.5. The model in question is called Laser Heating of a Silicon Wafer, and can be found in the Model Gallery. #resolventtip: Get the best performance out your 'General Extrusion COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH), Topology Optimization Electric Motor: General extrusion, Accessing Nonlocal Variables with Linear Extrusion Operators, How to Compute Distances Between Objects in COMSOL Multiphysics, Galleria dei Modelli e delle App di Simulazione, 2023 da COMSOL. Create a second line graph, showing the surface settlement, or vertical displacement, as a function of the distance from the wall. The Periodic Flow condition is used to set the velocity so it is identical at the inlet and outlet boundaries, allowing us to specify a pressure drop over a single unit cell. In such cases, we can use projection, integration, average, maximum, or minimum component couplings. Finite element model of the micro electrode array has been. An example of defining such a rotation matrix is detailed in this previous blog post. Here, the p-n junction in a diode is represented by a thin gap in the geometry. Where might you use it in your multiphysics modeling? Add a second distribution for the bottom boundary, and enter 2 for the number of elements. At the outlet, we want the species to be well mixed. Ivar. The applied heat load is described via a user-defined function, hf (x,y,t), that describes how the laser heat load moves back and forth along the x -axis in the global coordinate system. All you need are the time-dependent coordinates of the point where you would like to evaluate the temperature. A linear mapping built using a General Extrusion operator. When expanded it provides a list of search options that will switch the search inputs to match the current selection. A little calculus gives us the arc length of the parabola between the origin and the source point (x,y). Mapping of data defined on a cross section (left) around an axis of symmetry and into a volume (right). The company produces standard and custom aluminum extrusions for manufacturers in the appliance, medical equipment, transportation, and automotive markets, among others. Ce consentement peut tre retir tout moment. The Graphics Window: Effective and Beautiful Postprocessing, Generating Microsoft PowerPoint Slideshows from Your Models, Combining Adaptive Mesh Refinement with Data Filtering. COMSOL on Twitter: "Using the General Extrusion coupling operator in Your internet explorer is in compatibility mode and may not be displaying the website correctly. General Extrusions makes simple and intricate aluminum shapes through both long and short production runs. Examples of the General Extrusion Operator - COMSOL This approach helps avoid confusion if there is an extrusion or another operator also called genext1 or another variable called T in the second component. Thus, the second line y^iexpression is left blank. Online Support Center: https://www.comsol.com/support The same transforms can be implemented in three dimensions. Click the player button again to view all the parameter values in succession. The velocity field is given by u and v, the fluid velocity in the x and y-directions, respectively. The variable Disp is individually defined within each of the three domains, as shown in the figure below. Thank you for your time. This is reasonable to do since it is assumed that the flow field is independent of the species concentration. Now we will create a 1D plot and a line graph, with the wall diaphragm as the selection. Extrude - COMSOL Multiphysics listed if standards is not an option). In the results, how is Point 2 related to the general extrusion? The first boundary load is added for the horizontal soil boundaries. Settings used to map data from a boundary parallel to the xy-plane along the z direction. \frac{x_s}{2}\sqrt{1+4(\frac{x_s}{d})^2}+\frac{d}{4}\ln(2\frac{x_s}{d}+\sqrt{1+4(\frac{x_s}{d})^2}) = \sqrt{x_d^2+y_d^2}. In this example, since the x, y, and z-coordinates of the destination map are explicitly specified without any association with the coordinates of a geometric entity, it doesnt matter where we evaluate the General Extrusion coupling operator. Modeling Linear Motors or Generators in COMSOL Multiphysics From the graph below, can you see why the plot of arcext(T) on the right shows a radial variation? Extruding Data Along a Direction To begin, lets focus on how to replicate a Linear Extrusion operator with a General Extrusion operator. This approach is also useful in other analyses including structural contact or surface-to-surface radiation in heat transfer. It can be used for a variety of different purposes, examples of which are presented here. Lets consider a point on the disk at a distance of 0.5 inches from the center of the disk located at (0,0). A pressure constraint at a single point is used to gauge fix the pressure field. have some questions. Forming an assembly creates an identity pair between the wall soil and wall diaphragm boundaries. For such a unit cell model, the walls of the channels are set to the Wall, No Slip condition. CNC Machining for Aluminum Extrusions. Click plot to view the displacement at the different excavation depths. Segregated approach and Direct vs. Iterative linear solvers They are not necessarily pertaining to the x or y coordinates in the source or destination. The boundary load applies a force on the excavation side of the retaining wall, equal to (and therefore negating) the in-situ stresses, for any part of the wall that is below the virtual excavation depth. Thus, every point in the original domain is mapped along the positive x-direction by the specified displacement. Alle Rechte vorbehalten. -- Mapping of data between different components in the model to perform submodeling, Mapping between components to extract results on different geometries. An Outlet boundary condition is applied at the other end. The incident heat flux from the laser is modeled as spatially varying, with time varying coordinates for the location of the incident heat flux. Right-click study 1 to compute the model. From the Extrude from list, select Faces to extrude planar faces from the 3D geometry. Left: Temperature varies linearly from left to right. However, in general, we need to write the mathematical expression for the mapping. Now you know how to use the General Extrusion coupling operator to probe a solution at a moving point. An initial stress is added to the model as well to simulate the in-situ stresses in the x, y, and z directions. Similar to the first two, for the third strut, add the third strut boundary and change stage 2 to stage 3. Box 3488 Youngstown, OH 44513. General Extrusion Variable. Note that for axisymmetric components, variables can be viewed in 3D with a Revolution 2D data set in the Results node. Therefore, we have, Now we need to find the constants a,b,c,d,e, and f. Since source points (0, 0); (1.0, 0); and (0, 1.0) correspond respectively to destination points at (0, 0); (1.5, 0); and (0, 1.5), we get. The General Extrusion operator maps expressions defined on a source to an expression that can be evaluated on any destination geometry where the destination map expressions are valid. Therefore, we can greatly reduce our model by solving only for the fluid flow within one unit cell and patterning this flow solution throughout the modeling domain for the convection-diffusion problem. The settings for the General Extrusion operator and the definitions of the variable in the three domains. The working fluid is water with properties defined at room temperature and pressure. The same transforms can be implemented in three dimensions. General Extrusion, Linear Extrusion . Hi The General Extrusion feature is available in the model tree under Component > Definitions > Component Coupling. Select the faces that you want to extrude in the Graphics window. I would try to clarify further if necessary. To implement, define a General Extrusion operator on a boundary parallel to the xy-plane, with the z-expression blank for both the Source Map and a Destination Map. Only the data in the z-expression is mapped. Note that the operator name is kept to its default: genext1. General Extrusions is engaged in fabrication, anodizing, and powder coating, as well as aluminum finishing and machining. I tried to use your method but I failed. First add a size node to make sure the mesh is finer. The schematic diagram is shown in Figure 1. Similarly, on side 2, we need access to the electric potential V_1 on the other side of the junction. Here is an interesting question: How can we easily probe the solution at a point that is moving in time, but associated with a stationary geometry? There are some models. the destination map, not sure what the source frame should be. I have a 1D model (time dependent) and a 2D model (stationary). Gaining Understanding of Complex Phenomena with Virtual Laboratories, The Graphics Window: Effective and Beautiful Postprocessing, How to Use Maximum Likelihood for Parameter Estimation in COMSOL, Thank you for your Blog. indeed I do not believe I really understand what you intend to do. This will allow you to compare different cross-sectional data and evaluate measures such as maximum, minimum, and average over several cross sections. Because the source and destination objects have different dimensions, affine transformations are impossible. As the excavation reaches their depths, the struts are activated as long as the horizontal wall deflection is greater than what we allow it to be. Considering a variable defined on the xy-plane within a unit square centered at the origin, as shown above, it is possible to implement a variety of transforms simply via different destination maps, and leaving the source map unchanged. How to use the General Extrusion coupling operator to probe a solution at a moving point http://comsol.com/c/10mb Here is an interesting question: How can we easily probe the solution at a point that is moving in time, but associated with a stationary geometry?. I have the other model, where i would need this variable u, but this time, it is a 2D model, non time dependent. -- The same transforms can be implemented in three dimensions. Next, lets take a look at the settings of the General Extrusion coupling operator. Add boundary 8 and change the y-axis data expression to v and use millimeters as the unit. If the structural boundary conditions are not axisymmetric, we can save time by performing an axisymmetric thermal analysis in one component, and then mapping the temperature from the 2D axisymmetric domain to the 3D domain for structural analysis in another component. "Using the General Extrusion coupling operator in COMSOL: Dynamic probe http://t.co/q6jAnnc5HC" Your internet explorer is in compatibility mode and may not be displaying the website correctly. FIGURE 1. The corresponding normal current density for the Normal Current Density 2 node applied to edge 3 is -Js*(exp((V-genext1(V))/kTbyq)-1). The parameters J_s, q, k, \textrm{and } T represent the following, respectively: the saturation current density, the electronic charge, Boltzmanns constant, and temperature. Lets consider a laser heating example where you have a moving heat source, the laser, and a moving geometry. Now that the velocity field is defined throughout the modeling domain, the species concentration at the inlet is defined via the Inflow boundary condition. In this example, one expression is sufficient enough to uniquely relate any destination point in the square domain to a source point on the parabolic curve. Modeling an Excavation in COMSOL. In an upcoming blog post, we will walk you through how to use the operator to map cross-sectional data from one or several cross sections onto another cross section for geometries where the cross section dimensions do not change over the length of interest. Today, we have discussed how to use General Extrusion operators to create mappings for copying variables from one part of a simulation domain to another. This will enable us to define the flow field in the entire serpentine section. It is also possible to define the mapping in terms of coordinate systems. You can fix this by pressing 'F12' on your keyboard, Selecting 'Document Mode' and choosing 'standards' (or the latest version Take a look at the figure below. Multiscale Modeling in High-Frequency Electromagnetics, 2023 by COMSOL. It can be used for a variety of different purposes, examples of which are presented here. This variable should only exist on the . It contained both the high and low points for that academic semester; the lab portion was a lot of fun, learning about (read: playing with) the different soils and clays existing in the state of Georgia. Given an expression defined on a plane, e.g., the xy-plane, it is desired to map this . Considering a variable defined on the xy-plane within a unit square centered at the origin, as shown above, it is possible to implement a variety of transforms simply via different destination maps, and leaving the source map unchanged. General Extrusion coupling operator settings. From such source-destination pairs, one can infer the general mapping from superposition. Once the model has finished computing we can add some post processing to better view the results. If the mapping is affine, it is sufficient to know how some points in the source correspond to points in the destination entity. As you can see, they are in the same location but are different boundaries. The materials have already been created and set up for this model. How much easier it could have been had we only known about geomechanics simulation software. Mapping of data between different components in the model to perform submodeling, Mapping between components to extract results on different geometries. Extrusion operators can be used to access the electric potential on the other side of a junction. we first need to invert the expression L=\frac{x_s}{2}\sqrt{1+4(\frac{x_s}{d})^2}+\frac{d}{4}\ln(2\frac{x_s}{d}+\sqrt{1+4(\frac{x_s}{d})^2}) and write x_s in terms of L. Thats no fun at all! extrusion coupling error - COMSOL listed if standards is not an option). this defines if you should us a linear or general Extrusion or Projection I didn't mean to do integration, what i meant is something like: Thanks for replying. The same transforms can be implemented in three dimensions. To see how this General Extrusion operator maps variables, consider a plane stationary heat conduction problem with the left and right edges at temperatures of 300 K and 400 K, respectively. Each side of the junction becomes a source entity in one of the extrusion operators, as depicted below. Ce consentement peut tre retir tout moment. Tutti i diritti sono riservati. We want stress in the negative x-direction here. Extruding Data Along a Direction It can be used for a variety of different purposes, examples of which are presented here. For example, if you would rather follow the point on the geometry that corresponds to the focal point of the moving laser, you would enter the time-varying coordinates of the focal point of the laser. The settings for this feature are illustrated below. Clear the selection and add the middle strut, then change the expression from stage 1 to stage 2 to activate it only when the depth moves below the second strut. En fournissant votre adresse email, vous acceptez de recevoir des emails de COMSOL AB et de ses filiales propos du Blog COMSOL, et acceptez que COMSOL traite vos informations conformment sa Politique de confidentialit. This applies a varying species concentration over the inlet boundary. First a mapped mesh for the retaining wall domain. Examples of the General Extrusion Operator - COMSOL Multiphysics Your internet explorer is in compatibility mode and may not be displaying the website correctly. listed if standards is not an option). We can tag the different sides as 1 and 2, as illustrated in the figure below. Is it possible to "paste" two functions in COMSOL? Mapping of data defined on a cross section (left) around an axis of symmetry and into a volume (right). The video shown below uses the latter of the two strategies to model a 26-meter excavation. Then we add three distributions, one corresponding to each of the mapped mesh distributions. Linear Extrusion - COMSOL Multiphysics In addition to simply copying known quantities, these operators can be used to create nonlocal couplings between unknown variables, as illustrated in our p-n junction example. We can similarly evaluate the temperature at any other point. at an interface. It can be used for a variety of different purposes, examples of which are presented here. We are then looking at the problem of evaluating the temperature at a point that follows the rotating wafer material. Schematic of a microfluidic mixer that depicts the repeated unit cell and the inlet and outlet zones. When this check box is left unchecked, COMSOL Multiphysics assumes that we have explicit expressions for each coordinate of the source as functions of coordinates of the destination. For clarity, we did not use this trick here. Examples of the General Extrusion Operator - COMSOL Multiphysics For circular periodicity, a rotation matrix, not a linear shift, must be used in the destination map. But finally COMSOL basics is a PDE solver tool for a given subset of useful functions, of the type used for common physics (that fits in the global or coefficient form. For example, if the intermediate mesh is in 2D space, there is no z-expression field. I guess your problem is that there is no recalculation after defining genext1, and this error will not be prompted after the calculation. With the General Extrusion operator defined, we can now use it throughout the model. General Extrusions specializes in providing secondary fabrication operations to transition an aluminum extrusion to a finished component. The number of destination map expressions is the same as the space dimension of the intermediate mesh. the setting of the extrusion is shown in the attachment (the .PNG file ).